20 Shades of Grey: Highs and Lows of MerDer on 'Grey's Anatomy'

Grey’s Anatomy reaches the remarkable 200th episode milestone Thursday, October 10. The Highs and lows pretty much define the show over the past 9 seasons, and if the very real need for a bottle of wine and box of tissues with every episode is any indication, Grey’s certainly has run the gamut. We have practically witnessed 200 beloved characters die, developed affection for 200 new characters, lamented 200 marriages ending, celebrated 200 relationships beginning, and held our breath in the O.R. at least 200 times for the doctors of Seattle Grace, Seattle Grace-Mercy West, Grey Sloan Memorial Hospital. We are certainly no strangers to change. While their relationship is stronger than ever now, none have been more volatile and messed with our affections more than that of Meredith and Derek. Here are the top 20 relationship highs and lows of MerDer.